1. Field of the Invention
The present invention relates to a touch display, and more particularly, a touch display and a driving method of the touch display.
2. Description of the Prior Art
As technology advances, touch sensors are able to be embedded into a liquid crystal display to form an “in-cell” touch display. Because an in-cell touch display does not need an additional touch panel, it can reduce the thickness of the touch display and enhance the experience of touch control. Hence the in-cell touch display has gradually gaining its popularity in the development of display technology.
FIG. 1A shows a transmitting terminal conducting layer 102 and a receiving terminal conducting layer 104 in an in-cell touch display 100 of prior art. When a user touches the touch display 100, the capacitance C4 between the two conducting layers 102, 104 will change, thus the receiving terminal conducting layer 104 will generate a touch sensing signal TS having a magnitude different from a magnitude before the touch display 100 is being touched, and the receiving terminal conducting layer 104 will transmit the touch sensing signal TS to the touch sensing integrated circuit 106 so as to determine the position over which the touch display 100 is being touched by the user. FIG. 1B is a timing diagram of the signals of the touch display 100. After receiving a touch driving signal DS, the transmitting terminal conducting layer 102 generates an electromagnetic signal Tx, and the receiving terminal conducting layer 104 generates a touch sensing signal TS according to the capacitance between the two conducting layers 102, 104. In FIG. 1B, the broken line S0 refers to a touch sensing signal when the touch display 100 is not being touched, and the solid line S1 refers to a touch sensing signal when the touch display 100 is being touched. The difference between the broken line S0 and the solid line S1 is very small, thus the touch sensing signals before and after the touch display 100 is being touched are very similar. That is, the capacitances between the two conducting layers 102 and 104 before and after the touch display 100 is being touched are very similar. Therefore the touch display 100 is not very sensitive to triggers of the user, making improvement of the sensitivity of the touch display 100 an important issue.